Myeloid leukemia is usually subdivided into two groups: Acute Myeloid Leukemia (AML) and Chronic Myeloid Leukemia (CML). AML is characterized by an increase in the number of myeloid cells in the bone marrow and an arrest in their maturation. In the United States, the annual incidence of AML is approximately 2.4 per 100,000 and it increases progressively with age, to a peak of 12.6 per 100,000 adults 65 years of age or older. The CML is a malignant clonal disorder of hematopoietic stem cells. The median age at presentation is 53 years, but it occurs at all age groups, including children. The natural history of CML is progression from a benign chronic phase to a rapidly fatal blast crisis within three to five years or even earlier. The prognosis of CML is also poor in spite of vast advancement of clinical medicine (1). CD33 represents a specific and useful marker in the process of myeloid cell differentiation (2). Recent reports suggest that engagement of CD33 by monoclonal antibody induced apoptosis leading to growth inhibition of proliferation of AML and CML cells in vitro (2,3). Exploiting the myeloid specific expression of CD33, humanized anti-CD33 monoclonal antibody conjugated with anti-cancer drug has been tried in AML patients with significant success (4). Similarly, lymphoid leukemia is also subdivided in two groups: acute lymphocytic leukemia (ALL) and chronic lymphocytic leukemia (CLL). Lymphoid leukemia may affect both T and B cell lineages and are prevalent in children. With the extracts from Piper betel leaves anti-myeloid activity was claimed earlier (Patent filed no. PCT/INOO/00118 dated Dec. 12, 2000) and 3-o-p-Coumaryl quinic acid, an active factor for the treatment of AML and CML on 30.05.2002 U.S. provisional patent Application No. 60/384,163 (299/NF/2002.)
Hence, applicant's earlier findings are in direct consonance with the present patent filing on Chlorogenic acid (CA) isolated from the fractions of the betel leaf extracts for treating acute and chronic myeloid leukemia and lymphoid leukemia. Chlorogenic acid is known to have anti-allergic activity (5). CA also inhibits hepatic and renal glucose-6-phosphatase systems (6). CA is an inhibitor of epidermal lypoxygenase activity and TPA-induced ear inflammation (7). CA also renders inhibitory effects on TPA-induced tumor promotion in mouse skin (7). Anti-HIV activity of CA has also been reported (8). Although inhibition of tumor promotion has been attributed to CA, no anti-tumor activity on established tumors including anti-leukemic activity has not been reported for CA. In the present patent application, anti-leukemic activity and the anti-tumor activity of CA are claimed for the first time.
Piper betel leaves have a strong pungent aromatic flavour and are widely used in India as a masticatory. Generally, mature or over mature leaves, which have ceased growing but not yet become brittle are used for chewing. The basic preparation for chewing purposes consists of betel leaf smeared with hydrated lime and catechu to which scrapings of arecanut are added; flavorings such as coconut shavings, clove, cardamom, fennel, powdered liquorice, nutmeg and also tobacco are used according to one's taste. In some places prepared Piper betel leaf preparation is covered with silver or gold film. As a masticatory, it is credited with many properties: it is aromatic, digestive, stimulant and carminative. Medicinally it is useful in catarrhal and pulmonary infections; it is also used for poultices. The effects of chewing of betel leaves with arecanut and other adjuncts are the excitation of the salivary glands and the irritation of the mucous membrane of the mouth. The red coloration produced is due to a pigment in the arecanut, which manifests itself under the action of alkali in lime and catechu. A mild degree of stimulation is produced, resulting in a sensation of warmth and well being, besides imparting a pleasant odour. The most important factor determining the aromatic value of the leaf is the amount and particularly the nature of the essential oil present. Betel leaves from different regions vary in smell and taste. The most pungent is the Sanchi type, while the most mild and sweet ones are from Varanasi.
The betal leaves contain essential oils, the content of oil varies from 0.7 to 2.6 per cent depending upon the varieties of leaves. The oil consists of phenols and terpens. The higher the proportion of phenol oil, the better the quality. An isomer of eugenol named chavibetol (betel phenol; 4-alkyl-2-hydroxy-1methoxy benzene) is considered to be characteristic constituent of betel oil. Betel oil of Indian types contains as a predominant phenolic constituent and used in the treatment of various respiratory problems, either as a local application or by gargle. It has carminative properties. It exhibits in different actions on the central nervous system of mammals. The essential oil and extracts of the leaves possess activity against several Gram-positive and Gram-negative bacteria such as Micrococcus pyogenzes var. Albus, Bacillus subtilis and B. Megaterium, Diplococcus pneumoniae, Streptococcus pyogenes, Escherichia coli, Salmonella typhosa, Vibrio comma, Shigella dysenteriae, Proteus vulgaris, Pdseudomonas solanacaerum, Sarcina lutea and Erwinia carotorora. The essential oil and leaf extracts also showed anti-fungal activity against Asperigillus niger and A. Oryzae, Curvularia lunata and Fusarium oxysporum. The oil is found to be lethal in about 5 minutes to the protozoa, Paramaeceum caudatum (5). Steam-distillate of the leaves showed activity against Mycobacterium tyberculosis. 